The singer says she’s lost friends to the disease and that raising awareness about it is “close to my heart.”

She spoke to reporters Saturday just hours before she joins former U.S. President Bill Clinton, actress Brooke Shields and other celebrities at Vienna’s annual Life Ball, a huge party aimed at raising money for people with HIV and AIDS.

The event in and around city hall attracts crowds of revelers in risque attire that sometimes consists only of G-strings and glitter.